In a typical telecommunications switching center, the switching equipment is mounted in large cabinets anchored to the floor. The cabinet is supported by support feet which are spaced along the front and rear edges of the cabinet. The support feet are anchored by drilling holes in the floor and placing expansion anchors through the foot into the floor. After the holes are drilled in the floor, the cabinet, with the adjustable support feet attached, is placed where the holes in the floor correspond with the holes in the support feet. Bolts are then used to anchor the support feet to the floor, or threaded under floor structures, and nuts when using elevated floor systems.
One problem which has been encountered in the past when installing telecommunications switching cabinets is maintaining proper spacing between the support feet. A typical telecommunications switching cabinet has a series of mounting nuts which are welded to the bottom of the cabinet a fixed distance apart. The support feet are thread into these preset areas and are adjustable going up or down (used to level the cabinet). If the holes in the floor are measured incorrectly, the support feet will not anchor to the floor properly. Therefore it is important that the holes drilled into the floor are accurately located.
In the past, a floating template and measuring tape was used to locate the holes for the support feet in the floor. The floating template was shaped like the footprint of the cabinet and included pre-formed holes to mark the location of the holes for the support feet. The template would be located by measuring its distance from a known reference, such as a previously installed cabinet. Once the template was located, the holes for the support feet would be marked and drilled. This process would be repeated for each cabinet installed.
This method for laying out cabinets has a number of disadvantages. First, this method requires a great deal of care in making measurements to properly locate all of the support feet. Consequently, this method is relatively time consuming and costly. Further, no matter how much care is exercised, some measurement errors are bound to occur. When measurement errors do occur, the support feet will not be aligned properly and the cabinets cannot be anchored correctly. Consequently, it takes additional time to detect and correct the errors further increasing the cost of installing the cabinets. Furthermore, if holes are drilled incorrectly into concrete, the results can be devastating. If holes are drilled incorrectly into elevated floor systems, the floor could possibly be damaged beyond repair.
Accordingly, there is a need for an improved method of laying out telecommunications switching cabinets which decreases the time it takes to install the cabinets and reduces the number of errors.